BITUMEN AGEING IS ONE OF THE PRINCIPAL FACTORS CAUSING THE DETERIORATION OF ASPHALT PAVEMENTS [1]. ROAD BITUMEN, AS ALL ORGANIC SUBSTANCES, EVOLVE WITHTIME. IN FACT, THE MECHANICAL PROPERTIES AND THE CHEMICAL STRUCTURES OF BITUMEN CHANGEDIN AGING PROCESS (A KIND OF OXIDATION) [2]. FT-IRSPECTROSCOPY USED TO COMPARISON AND INVESTIGATION OF VARIATIONS IN BITUMEN FUNCTIONAL GROUPSDURINGOXIDATION PROCESS, AROAD AGEING, ALONG WITH TWO AGEING CONVENTIONAL TESTS: THE ROLLING THIN FILM OVEN TEST (RTFOT) AND THE PRESSUREAGEING VESSEL (PAV) [3]. OUR PURPOSE WAS TO COMPARE AND CORRELATE THE RESULTS OBTAINED BY FT-IR TECHNIQUES TOIMPROVE THE KNOWLEDGE OF BITUMEN’S REACTIVITY AND EVOLUTION SUBMITTED TO AGEING PHENOMENA. FT-IR SPECTRUM SHOWED THAT CARBONYL AND SULFOXIDE GROUPS AND CARBON DOUBLE BONDS DURING AGINGINCREASED. THE RESULTS OF PENETRATION AND SOFTENING POINT TESTS (ASTM D5 AND ASTMD36) INDICATE THAT IN AGING PROCESS, DUE TO WASTE OF GROUPS SUCH AS C=C, C=S AND C–C, AND GROWING FUNCTIONAL GROUPS SUCH AS C=O, O=C–O AND C–O, AND INCREASE IN POLAR GROUPS, THE INTERMOLECULAR FORCES INCREASED. AS A RESULT, PENETRATION VALUEOF BITUMEN DECREASES AND ITS SOFTENING POINT INCREASES; IN THE OTHER WORD, THE BITUMEN GETS TO BE HARD.